RU2736083C2 - Methyl and octyl tin stabilizer for production of pvc film - Google Patents

Abstract

FIELD: chemistry.SUBSTANCE: invention relates to a tin-organic heat stabilizer composition for a polyvinyl chloride film. Heat stabilizer composition for a polyvinyl chloride film contains the following in wt %: 40–75 octyl tin mercaptide and 60–25 methyl tin mercaptide. Octyl tin mercaptide contains, wt %: 90–98 tris-(mercaptide)octyl tin and 10–2 di-(mercaptide)dioctyl tin. Methyl tin mercaptide contains, wt %: 76–71 di-(mercaptide)dimethyl tin and 24–29 tris-(mercaptide)methyl tin. Described also is a film which contains an organotin heat stabilizer composition in amount of 0.5 to 3.0 wt % of the weight of the article.EFFECT: technical result is providing an optimum level of overall temporary thermal stability and color retention during calendering, as well as improved lubricating capacity and lower volatility.12 cl, 4 tbl, 4 ex

Description

Cross-references to related claims.

This application claims the advantage of US Provisional Patent Application No. 62/305013, filed March 8, 2016. Priority is hereby claimed on US Provisional Patent Application No. 62/305013, filed March 8, 2016, incorporated herein by reference.

This application claims the advantage of US Provisional Patent Application No. 15/419881, filed January 30, 2017. Priority is hereby claimed on US Provisional Patent Application No. 15/419881, filed January 30, 2017, incorporated herein by reference.

The field of technology.

The present invention relates to liquid organotin heat stabilizers for transparent, opaque and colored calendered rigid polyvinyl chloride (hereinafter - PVC); and in particular to a mixed discrete organotin stabilizer containing an octyltin mercaptide and a methyltin mercaptide.

State of the art.

The idea of mixing together two discrete organotin stabilizers is a new approach to solving two problems: first, increased efficiency due to good initial color and increased long-term thermal stability.

The second is compliance with the requirements of the European Union Regulation (REACH) legislation, that is, finished products based on PVC may not be labeled as containing "a substance of very high concern" due to the organotin stabilizer. The high performance monooctyltin based stabilizers are fully compliant with the European Union Regulation as well as the high performance dimethyl organotin stabilizers.

The abbreviation REACH: Registration, Evaluation, Authorization and Restriction of Chemicals means the European Union regulation dated December 18, 2006.

The requirements of the European Union Regulation relate to the production and use of chemicals and their potential effects on both human health and the environment.

The concept of using organotin stabilizers in rigid PVC as a heat stabilizer has been in practice since the 1950s. Tin heat stabilizers are the only heat stabilizers used for rigid PVC that allow the manufacturer to produce clear film. Other stabilizers cannot be used, since their refractive index does not correspond to the refractive index of PVC, which does not allow obtaining a transparent PVC film. Octyltin mercaptide is used to create a good initial color in transparent, opaque or colored calendered rigid PVC film. Methyl tin mercaptide is used to increase the long-term thermal stability (reduced flammability) of transparent, opaque or colored rigid calendered PVC films. Thus, methyltin mercaptide allows retaining color for a long time when processing rigid PVC films. Methyltin mercaptide also has low volatility (less vapor during processing), which is important in the manufacture of rigid PVC films.

Rigid PVC film is processed at temperatures above 400 ° F (204.4 ° C), the temperature at which PVC becomes unstable and degrades quickly without the use of a heat stabilizer. As noted, both methyltin mercaptide and octyltin mercaptide function as heat stabilizers in rigid PVC. However, none of the products by themselves can produce finished products with the desired properties. A new stabilizer is needed to provide the desired properties.

Disclosure of the invention.

The present invention provides a liquid organotin heat stabilizer for transparent, opaque and / or colored calendered rigid PVC. The organotin stabilizer of the present invention prevents PVC from degradation and discoloration when processing the calendered film. The stabilizer imparts transparency to colorless films and also retains color on colored films.

Since PVC is a chlorine-based plastic, it is inherently unstable during processing. The organotin stabilizer of the present invention prevents crosslinking and oxidation of PVC during processing. The stabilizer prevents the formation of HCl (hydrochloric acid) by replacing this defective area with a functional group from a tin-containing molecule.

The present invention includes various embodiments of the invention.

In one embodiment, the invention provides a composition comprising: 40 wt. % - 75 wt. % octyltin mercaptide; and 60 wt. % -25 wt. % methyltin mercaptide.

In this embodiment, the octyltin mercaptide contains 90 wt. % - 98 wt. % tris- (2-ethylhexyl mercaptoacetate) octyltin and 10 wt. % - 2 wt. % di- (2-ethylhexyl mercaptoacetate) dioctyltin; and methyltin mercaptide contains 76 wt. % - 71 wt. % di- (2-ethylhexyl mercaptoacetate) dimethyltin and 24 wt. % - 29 wt. % tris- (2-ethylhexyl mercaptoacetate) methyltin. In a preferred embodiment, the octyltin mercaptide contains 95 wt. % tris- (2-ethylhexyl mercaptoacetate) octyltin and 5 wt. % di- (2-ethylhexyl mercaptoacetate) dioctyltin; and methyltin mercaptide contains 74 wt. % di- (2-ethylhexyl mercaptoacetate) dimethyltin and 26 wt. % tris- (2-ethylhexyl mercaptoacetate) methyltin.

In other aspects of the invention, the weight ratio of octyltin mercaptide to methyltin mercaptide is not less than 60/40. Preferably, the weight percent of octyltin mercaptide may be in the range of 60 wt. % - 64 wt. % and methyltin mercaptide in the range of 40 wt. % - 36 wt. %.

More preferably, the weight ratio of octyltin mercaptide to methyltin mercaptide is 62/38.

In this embodiment, the octyltin mercaptide contains a monooctyltin mercaptide and dioctyltin, and includes 14 wt. % tin, methyltin mercaptide contains monomethyltin and dimethyltin mercaptide and includes 19 wt. % tin.

In another aspect of the invention, the weight ratio of octyltin mercaptide to methyltin mercaptide is not less than 75/25.

Organotin stabilizers according to the present invention are included in polyvinyl chloride articles, where the stabilizer of the present invention is from 3 wt. % up to 0.5 wt. % of the product.

Brief description of the illustrated embodiments of the invention.

The present invention will be easier to understand with reference to the following description in conjunction with the figures.

Some embodiments of the present invention are shown in the figures for illustration.

In the figures like numbers indicate like elements. However, it should be understood that the invention is not limited to the exact arrangements, dimensions, and tools shown:

FIG. 1 shows the color change of PVC in units of ∆E according to CIE (Delta-E according to CIE) at 0.8 PHR octyltin stabilizer (0.8 parts per hundred parts resin);

FIG. 2 shows the color change of PVC in units of ∆E according to CIE (Delta-E according to CIE) with a stabilizer based on octyltin 1.2 PHR (1.2 parts per hundred parts resin);

FIG. 3 shows the color change of PVC in CIE ΔE units (CIE Delta-E) at 1.6 PHR octyltin stabilizer (1.6 parts per hundred resin);

FIG. 4 shows the color change of PVC in CIE ΔE units (CIE Delta-E) at 2.0 PHR octyltin stabilizer (2.0 parts per hundred resin).

Detailed description of the illustrated embodiments of the invention.

The present invention includes a mixture of two discrete organotin stabilizers: octyltin mercaptide and methyltin mercaptide. Octyltin mercaptide is used for good color retention in transparent, opaque or colored calendered rigid PVC films. Methyltin mercaptide is used to improve the long-term thermal stability (reduced flammability) of transparent, opaque or colored rigid, calendered PVC films. Methyltin mercaptide also has low volatility (less vapor during processing), which is important in the manufacture of rigid PVC films. The two discrete organotin stabilizers are mixed together to form one homogeneous organotin stabilizer.

Blending two discrete organotin stabilizers is a novel approach to solving two problems. The first is increased efficiency due to good retention of the original color and increased long-term thermal stability.

The second is to comply with the European Union Regulation (REACH) legislation, ensuring that finished PVC products may not be labeled as containing “very high concern” due to the organotin stabilizer. High-performance monooctyltin-based stabilizers are fully compliant with the European Union Regulation as well as high-performance dimethyl organotin stabilizers.

The mixture of octyltin mercaptide and methyltin mercaptide according to the present invention provides an optimal level of overall temporary thermal stability and color retention in calendering operations.

Octyltin or methyltin, alone, do not provide the same effectiveness as the combination.

The results on the effectiveness of the mixture according to the present invention are much better than expected (or in other words, predicted) by averaging the effectiveness of only one of the components - octyltin mercaptide or methyltin mercaptide. Other additional benefits not anticipated (or anticipated) include improved lubricity and lower volatility.

The particular mixture of octyltin mercaptide and methyltin mercaptide is essential.

If the octyltin mercaptide were removed from the stabilizer, the good initial color of the finished rigid PVC film would deteriorate, possibly to the point where the finished product would become unusable, since good initial color and clarity are essential.

If the methyltin mercaptide were removed from the stabilizer, the long-term thermal stability would be reduced, resulting in material oxidation in the processing equipment due to processing temperatures above 400 ° F (204.4 ° C).

Accordingly, depending on the processing requirements, neither the octyltin mercaptide nor the methyltin mercaptide can be optionally substituted due to the specific function each of them performs: good initial color (octyltin mercaptide) and long-term thermal stability (methyltin mercaptide) ...

As an organotin heat stabilizer, the blend of the present invention can be used in any rigid PVC application requiring a heat stabilizer. Herein, the organotin stabilizer according to the present invention is preferably directed to the production of transparent, opaque and colored rigid PVC films.

At the same time, plastic can be used instead of PVC, and most plastics do not need a heat stabilizer for processing. Only PVC is required heat stabilizer for processing; therefore, PVC is preferred in any heat stabilizer application. The PVC article of the present invention includes a stabilizer composition that is 3% to 0.5% of the PVC article.

In one embodiment, the stabilizer composition of the present invention comprises 40% to 75% octyltin mercaptide and 60% to 25% methyltin mercaptide. A stabilizer mixture of this range finds application depending on processing requirements.

In a preferred embodiment, the stabilizer composition contains 60% to 64% octyltin mercaptide and 40% to 36% methyltin mercaptide.

In a more preferred embodiment, the stabilizer composition comprises 62% octyltin mercaptide and 38% methyltin mercaptide.

In the above embodiments, the octyltin mercaptide contains 90% to 98% tris- (2-ethylhexyl mercaptoacetate) octyltin and 10% to 2% di- (2-ethylhexyl mercaptoacetate) dioctyltin. Methyltin mercaptide contains from 76% to 71% of di- (2-ethylhexyl mercaptoacetate) dimethyltin and from 24% to 29% of tris- (2-ethylhexyl mercaptoacetate) methyltin.

In a preferred embodiment, the octyltin mercaptide contains 95 wt. % tris- (2-ethylhexyl mercaptoacetate) octyltin and 5 wt. % di- (2-ethylhexyl mercaptoacetate) dioctyltin; and methyltin mercaptide contains 74 wt. % di- (2-ethylhexyl mercaptoacetate) dimethyltin and 26 wt. % tris- (2-ethylhexyl mercaptoacetate) methyltin.

The finished stabilizer composition is an octyltin-based stabilizer containing monooctyl- and dioctyltin mercaptide and containing 14% tin, and a methyltin mercaptide-based stabilizer containing monomethyltin and dimethyltin and containing 19% tin.

One embodiment of the present invention comprises a stabilizer based on a mixture containing 50% octyltin mercaptide and 50% methyltin mercaptide (50/50).

Another embodiment of the present invention includes a stabilizer based on a mixture containing 70% octyltin mercaptide and 30% methyltin mercaptide (70/30).

In each of the stabilizer mixtures - 50/50 and 70/30, the proportion of octyltin mercaptide includes from 90% to 98% of tris- (2-ethylhexyl mercaptoacetate) octyltin and 10% - 2% of di- (2-ethylhexyl mercaptoacetate) dioctyltin; and the proportion of methyltin mercaptide comprises 76% to 71% of di- (2-ethylhexyl mercaptoacetate) dimethyltin and 24% to 29% of tris- (2-ethylhexyl mercaptoacetate) methyltin.

In some experiments, the 70/30 blend provided the best level of overall temporary thermal stability and color retention.

FIG. 1 is a table showing color over time (in minutes) for PVC products processed at 390 ° F (198.9 ° C) and containing 0.8 PHR (parts stabilizer per 100 parts resin). Or 0.8% stabilizer in a PVC product.

From left to right in FIG. 1 shows a control stabilizer (including only octyltin mercaptide); a stabilizer based on Mixture A (comprising a mixture of 75% octyltin mercaptide and 25% methyltin mercaptide - (75/25) according to one embodiment of the present invention; a stabilizer based on Mixture B (comprising a mixture of 62% tin mercaptide and 38% methyltin mercaptide - (62/38) according to another embodiment of the present invention; and finally a stabilizer based on Mixture C (comprising a mixture of 50% octyltin mercaptide and 50% methyltin mercaptide - (50/50) according to another embodiment of the present invention.

In each of the stabilizers, that is, Mixture A (75/25), Mixture B (62/38) and Mixture C (50/50), the proportion of octyltin mercaptide contains from 90% to 98% tris- (2-ethylhexyl mercaptoacetate) octyltin and from 10% to 2% of di- (2-ethylhexyl mercaptoacetate) dioctyltin; and the proportion of methyltin mercaptide contains from 76% to 71% of di- (2-ethylhexyl mercaptoacetate) dimethyltin and from 24% to 29% of tris- (2-ethylhexyl mercaptoacetate) methyltin.

FIG. 1 shows a color estimate (reflecting the change in color (E) over time in minutes) for particles of a PVC article that contain a stabilizer - Control, Mix A, Mix B and Mix C at PHR = 0.8.

These tables show that in the examples of PVC products included in this document, Blend B (62/38) provides the best level of overall temporary thermal stability and color retention.

FIG. 2 is a table showing color over time (in minutes) for PVC products processed at 390 ° F (198.9 ° C) and containing 1.2 PHR (parts stabilizer per 100 parts resin).

Or 1.2% stabilizer in a PVC product. From left to right in FIG. 2 shows a control stabilizer (including only octyltin mercaptide); a stabilizer based on Mixture A (comprising a mixture of 75% octyltin mercaptide and 25% methyltin mercaptide - (75/25) according to one embodiment of the present invention; a stabilizer based on Mixture B (comprising a mixture of 62% tin mercaptide and 38% methyltin mercaptide - (62/38) according to another embodiment of the present invention, and finally a stabilizer based on Mixture C (comprising a mixture of 50% octyltin mercaptide and 50% methyltin mercaptide - (50/50) according to another embodiment of the present invention. stabilizers, that is, Mixture A (75/25), Mixture B (62/38) and Mixture C (50/50), the proportion of octyltin mercaptide contains from 90% to 98% of tris- (2-ethylhexyl mercaptoacetate) octyltin and from 10% to 2% di- (2-ethylhexyl mercaptoacetate) dioctyltin; and the proportion of methyltin mercaptide contains 76% to 71% di- (2-ethylhexyl mercaptoacetate) dimethyltin and 24% to 29% tris- (2-ethylhexyl mercaptoacetate) Methyl tin. The table shows the color rating (reflecting the change change in color (E) over time in minutes) for particles of PVC product that contain a stabilizer - Control, Mix A, Mix B and Mix C at PHR = 1.2. The data of FIG. 2 show that in the examples of PVC products included in this document, the product, Blend B (62/38) provides the best level of overall temporary thermal stability and color retention.

FIG. 3 is a table showing color over time (in minutes) for PVC products processed at 390 ° F (198.9 ° C) and containing 1.6 PHR (parts stabilizer per 100 parts resin).

Or 1.6% stabilizer in a PVC product.

From left to right in FIG. 3 shows a control stabilizer (including only octyltin mercaptide); a stabilizer based on Mixture A (comprising a mixture of 75% octyltin mercaptide and 25% methyltin mercaptide - (75/25) according to one embodiment of the present invention; a stabilizer based on Mixture B (comprising a mixture of 62% tin mercaptide and 38% methyltin mercaptide - (62/38) according to another embodiment of the present invention; and finally a stabilizer based on Mixture C (comprising a mixture of 50% octyltin mercaptide and 50% methyltin mercaptide - (50/50) according to another embodiment of the present invention.

In each of the stabilizers, that is, Mixture A (75/25), Mixture B (62/38) and Mixture C (50/50), the proportion of octyltin mercaptide contains from 90% to 98% tris- (2-ethylhexyl mercaptoacetate) octyltin and 10% to 2% di- (2-ethylhexyl mercaptoacetate) dioctyltin; and the proportion of methyltin mercaptide contains from 76% to 71% of di- (2-ethylhexyl mercaptoacetate) dimethyltin and from 24% to 29% of tris- (2-ethylhexyl mercaptoacetate) methyltin.

The table shows the color estimate (reflecting the change in color (E) over time in minutes) for PVC particles that contain Control Stabilizer, Mix A, Mix B, and Mix C at PHR = 1.6.

The data of FIG. 3 using examples of PVC products show that the best level of overall temporary thermal stability and color retention is provided by Mix C (mix 50/50), then Mix B (mix 62/38).

FIG. 4 is a chart showing color over time (in minutes) for PVC products processed at 390 ° F (198.9 ° C) and containing 2.0 PHR (parts stabilizer per 100 parts resin).

Or 2.0% stabilizer in a PVC product.

From left to right in FIG. 4 shows a control stabilizer (including only octyltin mercaptide); a stabilizer based on Mixture A (comprising a mixture of 75% octyltin mercaptide and 25% methyltin mercaptide - (75/25) according to one embodiment of the present invention; a stabilizer based on Mixture B (comprising a mixture of 62% tin mercaptide and 38% methyltin mercaptide - (62/38) according to another embodiment of the present invention; and finally a stabilizer based on Mixture C (comprising a mixture of 50% octyltin mercaptide and 50% methyltin mercaptide - (50/50) according to another embodiment of the present invention.

In each of the stabilizers, that is, Mixture A (75/25), Mixture B (62/38) and Mixture C (50/50), the proportion of octyltin mercaptide contains from 90% to 98% tris- (2-ethylhexyl mercaptoacetate) octyltin and 10% to 2% di- (2-ethylhexyl mercaptoacetate) dioctyltin; and the proportion of methyltin mercaptide contains from 76% to 71% of di- (2-ethylhexyl mercaptoacetate) dimethyltin and from 24% to 29% of tris- (2-ethylhexyl mercaptoacetate) methyltin.

The table shows the color rating (reflecting the change in color (E) over time in minutes) for PVC particles that contain a control stabilizer, Mix A, Mix B and Mix C at PHR = 2.0.

The data of FIG. 4, using examples of PVC products, show that the best level of overall temporary thermal stability and color retention is provided by Mix B (mixture 62/38), and then Mix C (mixture 50/50).

Various changes and modifications to the stabilizer mixture described above will be apparent to those skilled in the art.

The embodiments of the invention specifically described above are given for illustrative purposes and are not intended to be limiting.

These and other advantages of the present invention will become apparent to those skilled in the art from the foregoing description. Accordingly, those skilled in the art will understand that changes or modifications may be made to the above described embodiments without departing from the general concepts of the invention.

For example, features detailed in some of the specific embodiments described above are considered interchangeable, and may be included in other detailed embodiments of the invention.

The specific parameters of any particular embodiment of the invention are described for illustrative purposes only. Therefore, it should be understood that this invention is not limited to the specific embodiments of the invention described herein, but is intended to include all changes and modifications that fall within the scope and spirit of the invention.

Claims (18)

1. Composition of a thermal stabilizer for a polyvinyl chloride film, including: from 40 wt.% to 75 wt.% octyltin mercaptide and from 60 wt.% to 25 wt.% methyltin mercaptide, wherein: octyltin mercaptide contains 90 wt% to 98 wt% tris- (mercaptide) octyltin and 10 wt% to 2 wt% di- (mercaptide) dioctyltin; and methyltin mercaptide contains from 76 wt% to 71 wt% di- (mercaptide) dimethyltin and from 24 wt% to 29 wt% tris (mercaptide) methyltin. 2. A composition according to claim 1, characterized in that the mercaptide is selected from one or more of the following substances: alkyl mercapatoacetate, mercaptoethyl carboxylate, and / or alkyl mercaptide. 3. Composition according to claim 1 or 2, characterized in that the mercaptide is 2-ethylhexylmercaptoacetate. 4. Composition according to any of the preceding paragraphs, characterized in that: octyltin mercaptide contains 95% by weight tris- (2-ethylhexyl mercaptoacetate) octyltin and 5% by weight di- (2-ethylhexyl mercaptoacetate) dioctyltin; and methyltin mercaptide contains 74 wt% di- (2-ethylhexyl mercaptoacetate) dimethyltin and 26 wt% tris- (2-ethylhexyl mercaptoacetate) methyltin. 5. Composition according to any of the preceding claims, characterized in that the weight ratio of octyltin mercaptide to methyltin mercaptide is not less than 50/50. 6. Composition according to any of the preceding claims, characterized in that the weight ratio of octyltin mercaptide to methyltin mercaptide is not less than 60/40. 7. Composition according to any one of the preceding claims, characterized in that the weight ratio of octyltin mercaptide to methyltin mercaptide is not less than 70/30. 8. A composition according to any of the preceding claims, characterized in that, in a weight ratio, the proportion of octyltin mercaptide is in the range of 60 wt% to 64 wt% and the proportion of methyltin mercaptide is in the range of 40 wt% to 36 wt%. 9. A composition according to any of the preceding claims, characterized in that the weight ratio of octyltin mercaptide to methyltin mercaptide is 62/38. 10. A composition according to any one of the preceding claims, characterized in that the octyltin mercaptide contains monooctyltin and dioctyltin and comprises 14% by weight of tin, and the methyltin mercaptide contains monomethyltin and dimethyltin and comprises 19% by weight of tin. 11. The composition according to any of the preceding claims, characterized in that the weight ratio of octyltin mercaptide to methyltin mercaptide is not less than 75/25. 12. A film comprising polyvinyl chloride, wherein the composition according to any one of the preceding claims is from 3 wt% to 0.5 wt% based on the weight of the article.

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